[pestes]

Yesterday, we had our front SCS air freeze up on us. Not sure how long it was frozen for but before I realized what had happened, I had flipped thermostat controls around in various ways (Hi/Lo, just fan, etc). Once I realized that with just the fan on, I was getting no air flow, it had become apparent that it was a freeze up.

I cleaned the filters under the stairs and then I ran the evap fan for a while to help the melt and then turned the thermostat to Off before heading to bed.

About 10 minutes later, the wife noticed that the A/C compressor on that unit was running. Even though the thermostat was in the Off position. And the evap blower was not running.

If I turned the therm back to Cool, the evap blower would come on. Turned back to off and the blower stopped but the compressor kept running.

I turned the thermostat back to cool, set it to a set point just above the current temp, and after a minute or two, the whole thing turned off as one would expect.


So I figured that the thermostat is going wonky on me.

However........

It was late, so I killed the breakers for that unit and went to bed again.

Then the wife notices that even though the rear air evap blower is not running, the rear compressor is!

Same story as the front - I set the set point to just above current temp, waited a bit, and it turned off.

I can't believe that I've had 2 thermostats fail in the same fashion on the same day. Or at least near enough to each other that it seems like they failed on the same day.

Is there any reason whatsoever that the compressor should ever be running without the evap blower? To me that seems like a sure fire way to have a freeze up, and I suspect it is why my front unit froze in the first place.